§2151. Business operations
If a trustee uses any part of the principal in the operation of a business of which, as trustee, he is a proprietor or a partner, the proceeds and losses of the business shall be allocated in accordance with what is reasonable and equitable in view of the interests of those entitled to income as well as of those entitled to principal, and in view of the manner in which men of ordinary prudence, discretion, and intelligence would act in the management of their own affairs.