Hi, I just need help with questions 4 and 6 thank you so much :)

Two cyclists 84 miles apart start riding toward each other at the samen time. one cycles 2 times as fast as the other. if they meet 4 hours later what is the speed (in miles) of the faster cyclists

Liz had 140 pens and inna had 100 pens. after inna gave liz some pens, liz had 3 times as many pens as inna. how many pens did inna give liz?

Give the functions f(x) = |x + 2| - 3, what is the domain? a,b,c, or d all real numbers x > 2 x < -2 all real numbers and x cannot equal to 2