An unknown additional charge q3 is now placed at point b, located at coordinates (0 m, 15.0 m ). find the magnitude and sign of q3 needed to make the total electric field at point a equal to zero. express your answer in nanocoulombs to three significant figures.

Ahowler monkey is the loudest land animal and, under some circumstances, can be heard up to a distance of 4.6 km. assume the acoustic output of a howler to be uniform in all directions and that the threshold of hearing is 1.0 × 10-12 w/m2. what is the acoustic power emitted by the howler

Name three different units of energy used to measure heat and describe what type of situations each is usually used.

Lymphocytes known as blastocysts make antibodies that fight infection. select the best answer from the choices provided t f