`2/(11xx13)` `= 1/11 - 1/13`

`2/(11x13) + 2/(13xx15) + 2/(15xx17) + ... + 2/(97xx99)`

`= 1/11 - 1/13 + 1/13 - 1/15 + 1/15 - 1/17 + ... + 1/97 - 1/99`

`= 1/11 - 1/99`

`= 8/99`

their parents?/going to/drive to the/country to visit/Are they

`->` are they going to drive to the country to visit their parents?

Fill in the blanks using gerunds or infinitives form of the verbs

1-Your tooth will stop......hurting......(hurt) if you take two of these

2-Women stop..working..(work) when they reach sixty

1. He is the oldest in his family.

2.He is the oldest in his family.

ta có R=\(\dfrac{15}{2}\)=7,5 \(\Omega\)

=> nếu tăng lên 3 vôn

=>I=\(\dfrac{18}{7,5}\)=2,4A