Jen and Ori are conducting an experiment to observe how sand and water absorb energy. They obtain two identical 1000-milliliter (mL) beakers, add 500 mL of distilled water to the first beaker, and 500 cubic centimeters (cm 3 ) of sand to the second beaker. They place both beakers on a hot plate that is set to medium heat. Thermometers are placed in each beaker and held with clamps. Both beakers are heated for seven minutes and then removed from the hotplate and cooled for an additional fifteen minutes. Jen and Ori record the temperature of each beaker at one-minute intervals. How could Jen and Ori have increased the reliability of their experiment?

they float because they are less dense than the water itself

something denser than water, like a rock, will sink to the bottom

rain is the best answer

the oldest known insects are believed to live around 400 millions ago as suggested by the fossil records.   some plants having woody stems also evolved during this time.

after the evolution of insects the first four legged species or the tetrapods evolved in shallow freshwater habitats from the intermediate species approximately 397 million years ago. the tetrapods went on conquering the land giving rise to amphibians, reptiles, mammals and birds.

the major split in tetrapods first occurred 340 million years ago branching off from amphibians.

363 million years ago when the carboniferous period began the insects started roaming on land and taking flights, following which the four limbed tetrapods adapted in the terrestrial habitat.