Answer:
the cyclists rode at 35 mph
Step-by-step explanation:
Assuming that the cyclists stopped, and accelerated instantaneously at the same speed than before but in opposite direction , then
distance= speed*time
since the cyclists and the train reaches the end of the tunnel at the same time and denoting L as the length of the tunnel :
time = distance covered by cyclists / speed of cyclists = distance covered by train / speed of the train
thus denoting v as the speed of the cyclists :
7/8*L / v = L / 40 mph
v = 7/8 * 40 mph = 35 mph
v= 35 mph
thus the cyclists rode at 35 mph
The brick will fall to the ground after 9 secs.
<h3>What are quadratic equations?</h3>
Given the equation for height as a function of time is h(t) = -16t2 + 1,296
The height of the brick on the ground is h(t) = 0. Substitute h(t) = 0 into the equation as shown:
Subtract 1296 from both sides
-16t² + 1,296 - 1296 = 0 - 1296
16t² = 1296
t² = 1296/16
t² = 81
t = 9secs
Hence the brick will fall to the ground after 9 secs.
Learn more on equations here: brainly.com/question/13763238
2.044 by just 0.004 units
Hi how are you today hopefully your well
The second part would be $700. I'm not sure how I would solve the first part. You should click the hint button.<span />