What is true about enzymes? a. enzymes provide the heat energy for a reaction. b. they lower the energy required for a chemical reaction. c. they slow the chemical reactions that take place in a cell. d. they combine with the reactants in a chemical reaction.

Asap timed! 1. ice core samples from glaciers ice caps contain bubbles of ancient atmosphere that are in layers based on age. what questions are scientists most interested in? a. how the amount of water vapor needed to make the ice has changed b. how the amount of ozone has changed over time.c. how the amount of ice in each layer has changed over time d. how the amount of carbon dioxide has changed over time 2. what produces milankovich cycles ? a. sunspots ams solar flare on the suns surface b. changes in the earths orbit c. gravitational changes bases on the position of the sun and the moond. cycles of vegetation that result in desert and rainforest conditions

Johnny rode his bike 4 blicks down the street to his friend's house once he got to his friend house and realized he could not cone out to play he turned aroubd and went back home.what is displacement for the total bike ride? how did you determine this? what could we use as a reference point to determine he was in motion during his bike ride? why can you use it as a reference point

What type of plant is good for a bioassay and where can i buy it? i only have a month.