to do it in mental math: you can ignore the zeroes in 400 for now.
4*14 = 4*10 + 4*4 = 40 + 16 = 56
now add the zeroes back on: 5600m
Answer:
the second one :)
Step-by-step explanation:
Answer:
Step-by-step explanation:
After removing one black marble:
Answer:
The surface area of the gift box is =
Step-by-step explanation:
The surface area of the cylinder can be calculated using this formula:
in this case, r is not a number, but rather an expression, which is r = .
The height of the gift box is twice the radius, which is h =
To get our curved surface area, we carefully put the expressions for h and r into the equation.
The surface area of the gift box is =