How long ago did homo sapiens first appeared in the fossil record? Identify the era in which this occurred.

Which of the following is used to measure weight? Newtons Liters Kilograms Meters

To which classification do compounds belong? A. heterogeneous mixtures B. pure substances C. homogeneous mixtures

An immersion heater of power J = 500 W is used to heat water in a bowl. After 2 minutes, the temperature increases from T1 = 85°C to T2 = 90°C.

Which statement describes an atomic nucleus? An atomic nucleus is negatively charged. An atomic nucleus has no electrical charge. An atomic nucleus consists of mostly empty space. An atomic nucleus contains most of the atom's mass.

Which of the three subatomic particles is responsible for determining the reactivity of an element?

Why is the monolith el capitan in yosemite national park more resistant to erosion than other igneous plutons in the park?

Block A weighs 1.20 N and block Bweighs 3.60 N. The coefficient of kinetic frictionbetween all surfaces is 0.300.

A cork able to float on water because it is

You have been asked to recommend a alternative source of energy that your town could use to generate electricity. Describe the renewable resource that you believe would be best for your town.

A clock moves past you at a speed of 0.9 c. How much time passes for you for each second that elapses on the moving clock? 0.436 s 1.15 s 2.29 s infinity