Hello everyone.
I am new to powering and I am facing something I can't understand it, however, I bought a multimeter called DT-830B to measure the voltage of my components, the below measurements seems to be weird to me
1) 3.7v battery when measuring it the multimeter display 4.8V
2) AC-to-DC adapter output 12v when measuring it the multimeter display up to 15V
any help will be appreciated.