If a sound source is producing sound with a steady pitch, and is vibrating with a frequency of one wave per 2 seconds, then how many times would it move back and forth in 20 seconds

An engineering team designs a new rocket that is faster and lighter than any other model being produced. however, the materials end up being so expensive that no company can afford to buy them. which step of the engineering process should have addressed this problem? a. know the background. b. evaluate the results. c. identify a need. d. do the work.

Seawater contains approximately 3.5%nacl by mass and has a density of 1.02 g/ml. what volume of seawater contains 7.5 g of sodium?

1. combine iron and copper (ii) sulfate solution. (hint: iron will form the iron (iii) ion) fe + cuso4 → 2. combine lead (ii) nitrate and potassium iodide solutions. pb(no3)2+ kl → 3. combine magnesium metal and hydrochloric acid solution. mg + hcl → 4. electrolysis (splitting) of water. h2o → 5. burning magnesium. mg + o2 →