Answer:
314 m²
Step-by-step explanation:
the formula for the surface area of a sphere (As) is
As = 4×pi×r²
the radius r (half of the diameter) is clearly indicated as 5m.
so, As = 4×3.14×5² = 4×3.14×25
I don't even need a calculator for this, as 4×25 = 100
so, As = 100×3.14 = 314
(you know, when multiplying by 10, the decimal point moves right one position. multiply by 100 it moves 2 positions, and so on).
Answer:
C
Step-by-step explanation:
If Ricardo started studying at 4 p.m and for sure will not stop until after 7 p.m, that means that he will be studying for 3 hours at least, and maybe even longer. So the time he will spend studying is at least 3 hours.
Therefore, x>3, where x is the time Ricardo will spend studying.
So first you have to do 18 multiply by 2/9. This gets you 4, next you multiply by 1/2. This gets you 2.
ANSWER: She will have 2 stamps left.
