Please help I only need part b and part c

Here is the answer.

Step-by-step explanation:

b) students are the frequency. so we need to add all the frequency.

5 + 4  + 7 + 10 + 4=30 students

c) here we need to use the summation.

total/ frequency= mean

6*5=30

7*4=28

8*7=56

9*10=90

10*4=40

we need to add them all= 244

total frequency= 30

mean = 244/30= 8.133333333...≈ 8 (this is a rounded of value as  in 0.13, 3 goes on repeating.

a net is a diagram that shows a “flattened” view of a solid. in a net, each face and base is shown with all of its dimensions. a net can also serve as a pattern to build a three-dimensional solid.

a pyramid is a three-dimensional object with a base that is a polygon and triangular faces that meet at one vertex.

" the net of a triangular pyramid consists of four triangles. the base here we are given of the pyramid is a equilateral   triangle, and the lateral faces are also triangles "

no

step-by-step explanation: