Add spaces: Thescientiststhenincreasedtheireffortstodevelopanefficient,cheapandreliabletypeofsolarcells.

Answer: The scientists then increased their efforts to develop an efficient, cheap and reliable type of solar cells.

Add spaces: Thiswillhaveadecisiveimpactonthevolumeofresiduesfromcoal-firedpowerplants,leadingtoasignificantdecline.

Answer: This will have a decisive impact on the volume of residues from coal-fired power plants, leading to a significant decline.

Add spaces: 21AndMosessaiduntoAaron,Whatdidthispeopleuntothee,thatthouhastbroughtsogreatasinuponthem?

Answer:
21 And Moses said unto Aaron , What did this people unto thee, that thou hast brought so great a sin upon them?