Which of the following is an example of a physical change ? a. a piece of iron being heated until it melts b. silver jewelry tarnishing c. a piece of wood burning

Working with si (metric) units for each of the following commonly used measurements, indicate its symbol. liter gram milliliter kilogram meter centigram milligram centimeter kilometer second millimeter milliseconds

Select the correct answer from each drop-down menu.describe what happens to a carbon-11 atom when it undergoes positron emission.the decay of a carbon-11 atom _1_, and this causes it to emit _2_.options for 1: > changes a neutron into a proton> changes a proton into a neutron> is hit with a neutron> reconfigures its protons and neutronsoptions for 2: > a negatively charged electron-sized particle> a positively charged election-sized particle> two atoms and several neutrons> two neutrons and two protons

Imagine that you push on a large rock. at what point does your effort change the rock’s mechanical energy?