Can someone help me with my homework ​

What number should be added to the expression x^2+3x+ in order to create a perfect square trinomial? 3/2 3 9/4 9

The chs baseball team was on the field and the batter popped the ball up. the equation b(t)=80t-16•16+3.5 represents the height of the ball above the ground in feet as a function of time in seconds. how long will the catcher have to get in position to catch the ball before it hits the ground? round to the nearest second

The los angels ram scored 26, 30, 48, and 31 pts in their last four games. how many pts do they need to score in super bowl liii in order to have an exact mean average of 35 pts over five games. write and solve and equation. use x to represent the 5th game.