Which Layer 1 troubleshooting issue can occur from not carefully ensuring compatibility with cable type and wavelength in use

Whats three fourths of 15(this is supposed to be in math but i clicked too fast)

Assume a class window with accessor method getwidth that accepts no parameters and returns an integer. assume further an array of 3 window elements named winarr, has been declared and initialized. write a sequence of statements that prints out the width of the widest window in the array.

What is a current gdp and what is a real gdp?