Sarah is making bread. She measures 0.6 kg of hot water into a bowl. The water needs to be at a temperature of
exactly 42°C in order for the yeast to function properly, but right now it is at 40°C. What mass of additional
water at 49°C should she add to make it the correct temperature? Assume no heat is transferred to the bowl or
to the outside air. And please show your work

Space-time metric ds2= -dt2+at2dx2+bt2dy2+ct2dz2 (a)how does the area of a rectangle with vertices at ( x=0, y=0, z=0 ), (1,0,0 ), ( 0,1,0 ) and (1,1,0 ) changes with time? (b) if a photon moving in the x direction starts from the origin at t=1, when does it reach x=l? (ds=0 for the trajectory of a photon.) (c) the proper time for a particle is defined by cd=ds. what is the proper time for a particle to move along the trajectory ( x(t)=t, y(t)=0, z(t)=0 ) from t=0 to 1 ? what is the condition on the parameter a so that the velocity of the particle never exceeds the speed of light ?

The diagram shows a series of volcanic island and a hot spot determine the direction of movement of the tectonic plate that for the island

This is for my 8th grade science class, i really don’t understand. can someone me? , lol.