What are four tools you can use to make quantitative observations

Quantitative is how many or a measurement. You can take a measurement with:
a ruler
thermometer
weight scale
stop watch
Hope this helps. 

A ruler, a bathroom scale, a clock, your heartbeat, a car speedometer, a car odometer, a photographer's light meter, a voltmeter, and a kitchen measuring cup can all deliver quantitative measurements.

He can play two games. 13/4=3.253.25*2=6.5

The anwser is: wave a has a greater pitch and frequency.