Evidence of a writing made as a record of an act, condition, or event is not made inadmissible by the hearsay rule when offered to prove the act, condition, or event if:
(a) The writing was made in the regular course of a business;
(b) The writing was made at or near the time of the act, condition, or event;
(c) The custodian or other qualified witness testifies to its identity and the mode of its preparation; and
(d) The sources of information and method and time of preparation were such as to indicate its trustworthiness.