Explanation:
Acids HCl HNO3 H2SO4
bases All oxides or hydroxides of metals
Choice A is correct.======Kinetic energy equation: KE = (1/2)(m)(v²)This tells us that KE is directly proportional to mass and the square of velocity. In other words, the more mass and more velocity an object has, the more kinetic energy.If an object is sitting at the top of a ramp, there is no velocity and therefore no kinetic energy. Choices B and D are wrong.A golf ball has more mass than a ping-pong ball, so a ping-pong ball would have less kinetic energy than a golf ball rolling off the end of a ramp. Choice C is wrong.Choice A is correct.
C. Mechanical, because temperature can cause solid objects to expand and contract, causing rocks to split apart.
Explanation:
Given that,
Mass of the object, m = 7.11 kg
Spring constant of the spring, k = 61.6 N/m
Speed of the observer, 
We need to find the time period of oscillation observed by the observed. The time period of oscillation is given by :

Time period of oscillation measured by the observer is :

So, the time period of oscillation measured by the observer is 5.79 seconds.
Plant trees on places where forests have been chopped down to restore damaged ecosystems. Encourage individuals to live in a way that is environmentally friendly. Create parks to conserve the rainforests and animals. Companies that operate in environmentally friendly methods should be supported.