Answer:
401.92 in²
Step-by-step explanation:
S.A. = 2πr²+2πrh
S.A. = 2π4²+2π4·12
S.A. = 100.48 + 301.44
S.A. = 401.92 in²
Answer
4 beats
80 divided by 20= 4 beats per second
a