If the SPF rating is 20 then it means it would provide 20 times the protection instead of no sunscreen and 20 times longer someone would take before the person started to burn or in this case 200 minutes.
Covalent bonds is the answer
Answer:
Those that “prefer” A charge; the Halogens and Chalcogens are good examples - Halogen MEANS salt forming, and even organic compounds can form salts; look up “tropylium ion”.
Explanation:
Answer:
the spiral type of galaxy
Answer: You can increase the weight, then test the speed, and make the weight normal and test the speed, and mark which one travels faster.
Explanation: This would test your hypothesis by comparing the speeds of the cars when more mass is added. Calculating the difference of the speed with more mass, and the speed with normal mass would give you your answer. A positive number would prove your hypothesis and a negative number would disprove it.