Why did I get this question wrong?

Step-by-step explanation:

∫₀³⁰ (r/V C₀ e^(-rt/V)) dt

If u = -rt/V, then du = -r/V dt.

∫ -C₀ e^u du

-C₀ ∫ e^u du

-C₀ e^u + C

-C₀ e^(-rt/V) + C

Evaluate between t=0 and t=30.

-C₀ e^(-30r/V) − -C₀ e^(-0r/V)

-C₀ e^(-30r/V) + C₀

C₀ (-e^(-30r/V) + 1)

I got the same answer.  Try changing the lowercase v to an uppercase V.

34.5 cm

step-by-step explanation:

generally for a circular segment of angle, θ° and radius r

arc length

= (θ/360) x circumference

= (θ/360) x 2πr

in our case, θ = 60°, π=3.142 and r = 33 cm

substitute into above formula

arc length

= (60/360) x 2(3.142)( 33) = 34.5 cm