Helen can write 15 postcards in one hour, while Kate can write 20 postcards. How much longer would Helen take to write 300
postcards than Kate?

Apersons beliefs and general outlook, which act like filters on the information they receive are called ?

3. a lunar exploration vehicle was created by a research team. it weighs 3,000 kg on the earth. it needs an acceleration of 10 m/s2 on the moon. in order to have the same acceleration, what will be the net force acting on the vehicle on the earth?

Which form of cell division creates the sperm and egg, resulting in half of the chromosomes as the other cells?