Via the half-life equation we have:

Where A is the amount initially and final amount after some time has passed, t is the time elapsed, h is the half life time and so:

Therefore there will be 2.8125 grams left after 140 seconds.
Answer:
352
Explanation:
.75 times 472 because .25 is sugar so .75 is watet
NH3 is a gas at room temperature. Solutions of "ammonia" are made by bubbling NH3 through water, so there's no "pure ammonia" unless you are talking about the gas.
For machines such as a rake the output force is less than the input force. If the input force of the rake is 10 newtons and the output force is 5 Newtons mechanical advantage is .5