H1b Visa consultancy salary percentage

My friend is planning to join a consultancy and work on % based salary. They mentioned the below percentage for him.

Each payroll , paying below payments to employee:

77.5% (Salary) + 9% (Retirement Savings) + 1% (workers compensation & Liability insurance) + 1% (Unemployment tax )+ 1% ( payroll taxes) + 0.5% WA State business exercise tax è 90%

10% is for employer.

I just want to understand is this a correct option to work on percentage like this? All the components are correct? Is employer doing some wrong calculations? Employee works at washington state and employer is in new york.