PLEASE help with organic chemistry

a chiral carbon has these substituents:
1. -CH2CH2CH2CH3
2. -CH2CH2CH3
3. -cyclo(C5H9)
4. -H

order the priorities from largest to smallest

Firstly, compare the atomic number of the atoms directly attached to the stereocentre - the group having the atom of higher atomic number receives higher priority. Straightaway, it can be seen that substituent 4 (atomic number 1) has the lowest priority.

For substituents 1, 2 and 3, the atoms directly attached to the stereocentre are the same (all carbon), therefore the atoms at distance two from the stereocentre are considered, i. e. the atoms bonded to the one directly attached to the stereocentre. Again, the atoms are the same (all carbon). Therefore, the atoms at distance three, four etc are considered until there is a difference.

At distance three, substituents 1 and 3 have a carbon atom and substituent 2 has a hydrogen atom. Substituent 2 has the lower priority. At distance four, substituent 1 has a hydrogen atom and substituent 3 has a carbon atom. Substituent 3 has the highest priority.

Order of priorities: 3>1>2>4

3. -cyclo(C5H9)
1. -CH2CH2CH2CH3
2. -CH2CH2CH3
4. -H

2. -CH2CH2CH2CH3
3. -CH2CH2CH3
1. -cyclo(C5H9)
4. -H