Meh, i honestly don't understand any of these

What is sin 7x/4 ? i need on this urgent trig

Which equation is true? i. 56 ÷ 4·7 = 82 ÷ (11 + 5) ii. (24 ÷ 8 + 2)3 = (42 + 9)2 neither i nor ii ii only i and ii i only

Olive's solar powered scooter travels at a rate of 30 miles per hour. what equation can she use to calculate her distance with relation to the time she traveled? h=hours m=miles 1. h=m+30 2. m=30h 3. m=h+30 4. h=30m