Answer:

Step-by-step explanation:
Total Surface Area of Cylinder = 
Given from the question, r = 7 cm and h = 15cm
Lets Substitute r and h into the formula to find the Total Surface Area of the cylinder.
Total Surface Area of Cylinder = 
Answer:
the angle is changing at a rate of 0.0375 rad/s when the time is t=8 seconds
Step-by-step explanation:
since the line D that starts from the spectator and follows the plane has the following equation
D² = x² + H² , where H= altitude of the plane , x= horizontal distance
then for x=v*t , where v=speed of the plane and t=time since the plane has passed overhead , we have for the elevation angle
tan θ = x/y = v*t /H
θ = tan⁻¹ ( v*t /H)
the rate of change in the angle of the spectator's sight θ with the time is
dθ/dt = 1/1+(v*t /H)² * (v/H) = (v/H)/[1+ (v/H)²*t²]
for t=8 seconds
dθ/dt = (875 ft/s/21000 ft)/[1+ (875 ft/s/21000 ft)²*(8 s)²] = 0.0375 rad/s
therefore the angle is changing at a rate of 0.0375 rad/s when the time is t=8 seconds
Answer:
what are the answers fir this question
If we take S=3, and R=2, then the answer is C, since 3*3*2 = 18, and 3+3+2 = 8, and 8 != 18