Answer:
If you still need the answer I think it's B
Step-by-step explanation:
Answer:
0.0008235
Step-by-step explanation:
8.235 x 10⁻⁴
10 to the exponent of a negative number means the decimal place is moved to the left to make the number smaller.
Move the decimal place 4 over the left.
0.0008235
its (a) because (a) is C(x)=3x4+30x and 9+21 is 30 so its 3x2+30
Estimating the area:

Calculating wallpaper:

we round up here because they will need a full roll to complete the room. Since they can't buy 7.92 rolls, they must buy 8.
Calculating cost: