The characteristics of cuboid and cube, their surface area, volume calculation formula. Please write one by one

The characteristics of cuboid: there are 6 faces, the opposite faces are equal, they are all rectangular, (sometimes the two opposite faces are square). There are 12 edges, the length of the opposite edges is equal. There are 8 vertices. Each face has 4 right angles. Surface area = (length x width + length x height + width x height) x2

Summarize the formula of triangle, square, rectangle, parallelogram, trapezoid, circle and perimeter

The perimeter formula is: Three: the sum of three sides, positive: side length multiplied by 4, length: (length + width) X2, flat: (length + width) X2, circle: π D
1 triangle
The two opposite sides of a parallelogram are equal, and one is parallel and equal
The four corners of a rectangle are right angles, and the diagonals are equal, and the diagonals are equally divided
The four corners of a square are right angles, and the diagonals are equal. The diagonals bisect each other. The four sides are equal, and the diagonals bisect the inner angles
A set of opposite sides of a trapezoid that are parallel and do not want equal diagonal lines
The circle I is now surrounded by a circle whose diameter passes through a dot

What are the characteristics of rectangle, square, parallelogram, trapezoid, triangle and circle?

Rectangle: the corresponding side length is equal, there are four corners Square: the four sides are completely equal, there are four corners parallelogram: the corresponding side length is equal, the figure is inclined, there are four corners trapezoid: there are four corners can be divided into isosceles trapezoid and unequal isosceles trapezoid isosceles trapezoid, among which there are two waist equal triangles: there are three angles, the inner angle sum is 180 ° circle: the round seems to have no characteristics

A general formula for sector area of rectangular square triangle parallelogram trapezoid circular ring?

Rectangle: length * width
Square: side length * side length
Triangle: 1 / 2 * bottom * height
Parallelogram: bottom * height
Trapezoid: (upper bottom + lower bottom) * height / 2
(in fact, the trapezoid formula can be used for all the above five formulas. For a rectangle, the upper bottom equals the lower bottom, for a square, the upper bottom equals the lower bottom equals the height, for a triangle, the upper bottom or the lower bottom equals zero, and for a parallelogram, the upper bottom equals the lower bottom.)
Circle: Π * R ^ 2
Ring: Π * (R ^ 2-r ^ 2), R is the radius of large circle, R is the radius of small circle
Sector: 1 / 2lr = n Π * R ^ 2 / 360, l is arc length, n is degree of circle center angle, R is sector radius

A total of 288 trees were planted in the three classes of grade 6 of Xiangyang primary school. It is known that there are 47 students in class 1, 51 students in class 2 and 46 students in class 3. The number of trees planted by each student is the same. How many trees are planted in each class
Please list the formula and tell me about it~

Trees per person = 288 / (47 + 51 + 46) = 2
So class one tree planting = 47 times 2 = 94
Second class tree planting = 51 times 2 = 102
Tree planting in class 3 = 46 times 2 = 92

Young pioneers planted 50 trees in the fifth grade, which is exactly 5 / 6 of the number of trees planted in the sixth grade
Solve the equations and write the relations

There are x trees in Grade 6
5X/6=50
X=50*6/5
X=60
60 trees in Grade 6

There are three classes in Grade 6 to plant trees. The ratio of the trees planted in class 1 to class 2 is 5:4, and the ratio of the trees planted in class 2 to class 3 is 3:2. There are 105 trees planted in the three classes. How many trees are planted in class 1, class 2 and class 3?

Class 1: Class 2 = 5:4 = 15:12 class 2: Class 3 = 3:2 = 12:8 class 1: Class 2: Class 3 = 15:12:8105 × 1515 + 12 + 8 = 45 (trees) 105 × 1215 + 12 + 8 = 36 (trees) 105 × 815 + 12 + 8 = 24 (trees) answer: Class 1: plant 45 trees, class 2: plant 36 trees, class 3: plant 24 trees

65 trees were planted in grade five, and 12 trees were planted in grade six three times less than that in grade five,

65×3-12
=195-12
=183 trees
A: 183 trees were planted in grade six
You can ask me if you don't understand my answer!

There are 100 trees planted in five classes in Grade 6. It is known that the number of trees planted in each class is different, and the ranking from the most to the least is class 1, class 2, class 3, class 4 and class 5. The number of trees planted in class 1 is the sum of the number of trees planted in class 2 and class 3, and the number of trees planted in class 2 is the sum of the number of trees planted in class 4 and class 5. How many trees can be planted in class 3 at most? I'm so anxious,
The standard of charging electricity fee in a certain place is: if the monthly electricity consumption does not exceed 50 kwh, charge 50 jiao per kwh; if it exceeds 50 kwh, charge 8 jiao per kWh for the excess part. In a month, customer a paid 3 yuan and 30 cents more than customer B. how many kilowatt hours did customer a and customer B use this month?
Here's another question!

According to the meaning of the question, there are: a + B + C + D + e = 100; - - - - (1) a > b > C > d > e; a = B + C; b = D + E; if the second class is more than the third class, that is, B = C + X, then x > 0; a = B + C = 2C + X; --- (2) B = D + e = C + X; --- (3) (2), (3) substituting (...)

There are three classes in Grade 6 to plant trees. The ratio of the trees planted in class 1 to class 2 is 5:4, and the ratio of the trees planted in class 2 to class 3 is 3:2. There are 105 trees planted in the three classes. How many trees are planted in class 1, class 2 and class 3?

The characteristics of cuboid and cube, their surface area, volume calculation formula. Please write one by one