A space traveler whose mass is 115 kg.

Who can you think of that has an a in their first name and a b in their last name?

Did the universe cool off or get hotter as it expanded after the 'big bang"?

17 a tourist was planning a trip by car for travelling at some constant speed for 2.5 hours. however, he found that if he increases the speed by 20 km/h he can cover the same distance in 30 minutes less time than it was planned. what was the planned speed of the tourist, in km/h?