Was Smith and Smith required to hire the original four applicants based on the law?

1. Four applicants for jobs at Smith and Smith Legal Services received a letter from the company indicating that if they took and successfully completed the Massachusetts Bar Exam, they would be offered employment by the company.  All four applicants studied, registered for, and successfully passed the exam.  When they presented documentation to Smith and Smith indicating their successful completion of the exam, they were told that the positions were no longer available as the company had already hired other lawyers.  Was Smith and Smith required to hire the original four applicants based on the law?

2.  Donavan Painting Company agreed to install siding on Anderson’s home at 431 Main Street.  Due to a mix up, Donavan installed the siding on Murray’s home at 431 Main Terrace instead.  Murray was an accountant and he worked from home in an office above his garage.  He watched Donavan pull up and begin to work on the house.  He stayed in his office and didn’t leave until Donavan finished with the work.  Later he received a bill from Donavan but he refuses to pay.  Is he required to pay?

3.  For many years Gary provided yard services to Mr. Restivo during the spring and summer months.  After the first snowstorm in October 2020, Mr. Restivo notified Gary that he no longer wanted to use him for his yard services. In April of 2021, Gary started to provide services again to all of his customers.  On April 10 at 6:45am Gary arrived and worked on Mr. Restivo’s yard. When Mr. Restivo woke up at 9:00am, he found that his lawn had been cut and his bushes were trimmed.  He also found a bill from Gary indicating that he owed him $300.  Mr. Restivo refused to pay.  Is he legally required pay the bill?