Divide and simplify if necessary.
1. 2 ¾ ÷ 2 ½ = __________
2. 3/7 ÷ 3/5 =____________
3. 12/13 ÷ 8/39 =_________
3. Divide 23 and 2 ½ _____________
4. How many 2/3 cm can be cut from a 60 cm piece of cord? _____________​