Which of the below statements is true of the following text?

①The research team made a different assumption about the electrical properties of primordial black holes. ②They postulate that ③their model shows if ④a primordial black hole forms with a small dark electric charge, ⑤it should be temporarily stabilised before finally exploding.

What type of connector is ‘at present’ in the following text?

At present, overpumping groundwater is the largest contributor to rates of terrestrial water storage decline in drying regions, significantly amplifying the impacts of increasing temperature, aridification, and extreme drought events

What type of connector is ‘since’ in the following text?

Patrolling is a dangerous activity, since chimps of different groups risk death in an encounter.

What type of connector is ‘showed’ in the following text?

As physicist Stephen Hawking showed in 1970, the lighter a black hole is, the hotter it becomes and the more particles it emits through Hawking radiation.