Problems with Sketch on Mega 2560

I have the code that was made for this project I have gone over it and modified it a little bit. Tested the impact tester and it worked but now we want to incorporate the sensor (HC-SR04) with the LCD screen, and I am having trouble doing so. I have attached the code that goes with the impact tester , and the other two are the ones we want to incorporate labeled Height_Sensor 1 and Liquid_Crystal 1 .

Impact_tester 1.docx (16.6 KB)

Height_Sensor 1.docx (11.4 KB)

Liquid_Crystal 1.docx (10.5 KB)