I think it would take 24 hours or 10 hours
explanation: if you have 4 hours from Erin, and 6 hours from Cathy, it’ll most likely be 10 hours because you’re trying to find out the total amount. (keyword: together & how many)
Do NOT search the link they WILL hack you
It's B cause it's open upwards.
The equation represents height as a function of time.
The bullet was in the air for 75 seconds.
The equation is given as:

The time spent in the air is the time it takes the bullet to land on the ground.
When the bullet is on the ground, the height is:

So, we have:


Factor out t

Split
or 
represents when the shot is fired.
So, we solve for t in 
Collect like terms

Divide both sides by 16

Hence, the bullet was in the air for 75 seconds
Read more about height and time at:
brainly.com/question/2261757
1.41 is greater than 1.39
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